Steering Magnetic Nanoparticles by Utilizing an Adjustable Linear Halbach Array

Abstract

Magnetic nanoparticles offer numerous promising biomedical applications, e. g. magnetic drug targeting. Here, magnetic drug carriers inside the human body are manipulated towards tumorous tissue by an external magnetic field. However, the success of the treatment depends strongly on the amount of drug carries, reaching the desired tumor region. This steering process is still an open research topic. In the proposed paper, an adjustable linear Halbach array to steer magnetic nanoparticles is investigated numerically using COMSOL Multiphysics. This Halbach array produces a relatively large region of a high magnetic field, while having a strong gradient. This results in a strong magnetic force, trapping many particles at the magnet. To avoid particle agglomeration, the Halbach array is rotated to its weak side. In this context, the force on the nanoparticles is evaluated for different magnet rotation angles. Comparing the weak and the strong magnetic side, the maximum and average magnetic force is a factor of 2.1 and 1.5 higher, respectively. Overall, the results depict the magnetic force and, thus, the region where the particles are able to get washed out, can be adjusted.